We visited the Olav's mine near Roros today. Copper has been mined in this area since the 1600's. This area shows the residue left over after the refining process. Cotton grass seems to be the only plant that will grow there.
I used to be fascinated by cotton grass as a child...can't say I know anything more about it now than I did then...must look that up too!! Lovely clarity of the cotton buds!